ISDT Air A4 & A8

Batteries and Chargers Chargers
1

I’ve been looking for new AA/AAA chargers for travel (I use AA batteries in my scubadiving flashlight), that would be as minimal as possible, AND will have USBC, and ideally one that can take more power to charge at 1A vs 0.5A even in an 8 battery configuration. Took me some time to look it up - ut eventually found the ISDT Air series.

This charger is as small as I’ve ever seen - it’s literally the size of a case for 4/8 batteries, only it can also charge. it has led indicators for status, but what’s even more cool is that it has BT so you can connect an app from your phone to get full data, which is very cool.

Also - thanks to BT, it can do firmware updates. as I got it in insisted on doing FW update on both. Maybe this is to fix some problems a few people reported on in some of the reviews Ive seen (wrong decisions on termination of charging). For the time being mine charges well, and the app is a nice touch for such a small travel charger.

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2

Hi @Slartz, did you buy the A4 Air? What app do you use it with? On iPhone or Android?

I bought an A4 Air a couple months ago. Generally, it works, but over time I ran into several problems with it:

  1. The (originally) suggested app “ISDLink” did not work properly, so I contacted ISDT. They then recommended the app “Polying”, which I then installed. This works, so far. It installed newer firmware on the A4 Air. But …

  2. The A4 Air cannot recharge older NiMH AA’s which have increased internal resistance. This is a shame, because such cells could still be used well with equipment that doesn’t need high currents.

  3. Automatic cell chemistry recognition is unreliable. You better ALWAYS(!!!) verify and if needed correct the settings in the app.

  4. Input is specified as 5-9V 1.5A, but powered with 5V, it cannot recharge LiFePo4 or Li-Ion cells. It needs 9V USB power for this sort of cells.

  5. Recently, I bought a 8-pack of rechargeable 1.5V Li-Ion (XTAR 1.5V AA CLR 4300). Nominally, the A4 Air supports 1.5V rechargeable Li-Ion cells - you can select them from the cell type selector in the app - but as already expressed, the automatic cell type recognitions isn’t reliable. When I inserted discharged 1.5V Li-Ion cells into the charger, it identified different cell types in the 4 slots.

I then selected 1.5V Li-Ion in the app to correct the cell type, one slot after the other - but the unit did not switch to 1.5V Li-Ion on all slots! It did not accept my selection on some slot!

I then reported this to ISDT asking for a firmware update to correct this, but they answered

If it cannot be recognized, that means it is not compatible. Currently, this charger is not compatible with all 1.5V lithium batteries.

That’s disappointing :-1: because it means that I have to take along 2 different chargers on trips where I need to recharge LiFePo4 as well as 1.5V Li-Ions.